Pretty much what Ken said. You can move most of the plants you've got if you want to rearrange. Do keep in mind, it's already quite late in the season to be transplanting (hot, hot, hot), so they'll need proper watering and they may take longer to recover. Just do it.

I agree with most of Ken's suggestions but have to wonder, will the bed have curved edges or will it be rectangular? From your photo/design above I'm assuming curved edges which is good for a couple of reasons. There's no way for us to determine how far away the nearest source of water is located. Will providing supplemental water during dry spells become an issue for things that need it? I have most everything on your diagram growing in my various mixed beds and all have been thriving since 2007. I supply supplemental water only during severe drought and only to my hydrangeas & astilbe/false spirea.

Of the plants you listed, the only one that generally does well in either sun or shade where I am (south central New England) is heuchera/coral bells. Mine are growing on the east side of my house in part shade & part sun and seem to thrive.

That looks exciting, good luck and don't forget to mulch.

My only comments:

there are all different kinds of shade, and it seems yours is a light shade from neighboring trees so not much of a problem. The dianthus, gaillardia, and maybe the salvia are the only ones I see that demand full sun to do their best.

The monarda, rudbeckia, and Shasta daisy will spread out into good sized clumps so make sure they have some extra room to grow.

check the hardiness on the orange sedge

Leave some space for later additions and divisions. Some of your plants will be easy to divide and multiply and you might want to repeat them a little more through the border once things become established or fade away. I like to repeat a few things here and there to bring the whole border together.

You have a nice selection of perennials, it will look even better next year when they take off!

Looks to be a fantastic garden and the butterflies will thank you for it!!!!!!

Thanks so much all! I am tilling, Ken, so I went out and doubled the marked space in white before any of the utilities got here to mark - why rent the machine again in the fall when I want to plant bulbs? I appreciate it - you saved me some money! I do want them all crowded together, but I'll give them a little more space to grow - I have an aquilegia being choked to death by virulent rudbeckia out front, so better to add more plants if there's space than not give them enough room to get a good start.

Laceyvail, I know it's super late to be planting, but my garden centers are slow to get in late bloomers, and I will baby the new plantings since I'm home for the summer. I appreciate the reassurance I can always rearrange!

Gardenweed, I've been thinking of moving the coral bells more to the shady side - I will do that before I plant. The bed is only about 100' from my house and I have a long hose, so I should be good for supplemental watering. I water my hostas and astilbes in front regularly, and everything else only when we've gone a week or so without rain. Since I'm planting these so late, I'll keep a close eye on their water needs for a bit. The bed will have curved edges in the front, and I may not edge the back just yet - I'm thinking of maybe adding some holly or varigated dogwood or shrubby St. John's Wort in the back later on.

Katob, I'm happy to hear the monarda will spread - it's my first time growing that and it's so huge - I'm excited to see it bloom! I like the idea of dividing and repeating, thanks!

Shillanorth, thank you - the butterflies and bees have already found the plants, even in their pots, and are fluttering around like crazy. That's why I picked most of them!

I really appreciate the feedback, everyone! I'll post pictures when I get it all in the ground.